SRJC 2008 JC2 Prelim H2 Paper 1 with answer key

1 SERANGOON JUNIOR COLLEGE General Certificate of Education Advanced Level Higher 2 CHEMISTRY 9746/01 Preliminary Examination 28th Aug 2008 Paper 1 Multiple Choice 1 hour Additional Materials: Data Booklet Soft clean eraser Soft pencil (type B or HB is recommended) OMR Answer Sheet READ THESE INSTRUCTIONS FIRST Write your name, index number on the OMR Answer Sheet in the spaces provided. Write in soft pencil. Do not use staples, paper clip, highlighters, glue or correction fluid. There are fourty questions in this paper. Answer all questions. For each question, there are four possible answers A, B, C and D. Choose the one you consider correct and record your choice in soft pencil on the separate OMR answer sheet. Read very carefully the instructions on the OMR answer sheet. You are advised to fill in the OMR Answer Sheet as you go along; no additional time will be given for the transfer of answers once the examination has ended. Each correct answer will score one mark. A mark will not be deducted for a wrong answer. Any rough working should be done in this question paper. You may use a calculator. This document consists of 18 printed pages and 0 blank page. SRJC 2008 9746/01/Prelim/2008 [Turn Over

2 Section A For each question there are four possible answers, A, B, C and D. Choose the one you consider to be correct. 1 In a titration experiment, 30 cm 3 of 0.05 mol dm -3 phosphorous acid, H 3PO3 was found to exactly neutralise 15 cm 3 of 0.20 mol dm -3 aqueous sodium hydroxide. Using this information, deduce the formula of the salt formed in the neutralisation process. A NaH2PO3 B Na2HPO3 C Na3PO3 D Na3PO4 2 G is an element in period 4 of the periodic table. The ionisation energies of the first 13 electrons in element G is plotted against the order of removal of electrons as shown in the diagram below: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 Order of electrons removed from X Log (Ionisation Energy) What is the formula of the compound formed when G reacts with oxygen? A GO B GO2 C G2O D G2O3 3 Which graph is obtained when pV is plotted against density, ρ, for a fixed amount of an ideal gas at constant temperature? SRJC 2008 9746/01/Prelim/2008 [Turn Over Order of electrons removed from G

C H H C H N H H C O OH I I OHO I I qp r s 3 A B C D 4 The thyroid gland concentrates iodine and uses it to produce thyroxine, which is a hormone that controls the metabolic rate. Thyroxine What are the values of the bond angles p, q, r and s? p q r s A 180° 90° 180° 90° B 105° 109.5° 107° 120° C 180° 90° 120° 180° D 105° 90° 107° 180° 5 2-bromopropane undergoes nucleophilic substitution with aqueous NaOH via the following mechanism. SRJC 2008 9746/01/Prelim/2008 [Turn Over pV ρ pV ρ pV ρ pV ρ

4 H3C C H Br CH3 C H CH3 H3C + Br-slow C H CH3 H3C + OH- H3C C H OH CH3 fast Which of the following diagrams represent the energy profile diagram of the reaction? A B C D 6 For which equilibrium does Kc has no units? A C (s) + H2O (l) CO (g) + H2 (g) B H2 (g) + I2 (g) 2HI (g) C Cu2+ (aq) + 4NH3 (aq) Cu(NH3)42+ (aq) D 2NO2 (g) N2O4 (g) 7 A titration curve is shown below: SRJC 2008 9746/01/Prelim/2008 [Turn Over reaction pathway energy reaction pathway energy reaction pathway energy reaction pathway energy

5 To which pair of substances could this curve apply? A NaOH titrated with HCl B KOH titrated with CH3COOH C NH3 titrated with HCl D NH3 titrated with CH3COOH 8 A sparingly soluble barium salt dissociates in solution according to the equation: BaL2(s) Ba2+(aq) + 2L-(aq) If the solubility product of Ba L2 is q mol 3 dm -9, what is the concentration of L- at equilibrium in a saturated solution of BaL2(aq)? A 3 q B 2 3 1      4 q C 3 1 q D 3 1      4 q 9 Aureomycin is a powerful antibiotic. Aureomycin has the structure shown below: SRJC 2008 9746/01/Prelim/2008 [Turn Over Volume of acid added/ dm3 pH 8 2.5 13

2 1H 6 OH Cl O HO CH3 OH OH O C O NH2 H N CH3 CH3 How many optical isomers does Aureomycin have? A 5 B 10 C 16 D 32 10 An organic compound, on heating with an excess of hot concentrated acidic KMnO4(aq), produces CH3COCH2COCH2CH2COCH2COOH and CH3COCH3. What could the organic compound be? A B C H3C C(CH3)2 CH3 O CH3 H3C CH=C(CH3)2 C D CH3 CH2CH=C(CH3)2 HO CH2CH3 C(CH3)2OH 11 Deuterium, D, is the isotope of hydrogen. How many deuterium atom(s) is/are incorporated into a molecule of Linalo-ol when it is reacted with bromine in heavy water, D2O? SRJC 2008 9746/01/Prelim/2008 [Turn Over

7 Linalo-ol A 0 B 1 C 2 D 3 12 A halogenoalkane, M, can give a primary amine by heating it in a sealed tube with ammonia. A nitrile, N, can give a primary amine by reduction. Which of the following pairs of M and N give the same amine? 13 Which inorganic reagent may be used to distinguish between phenol and ethanol? A aqueous Na2CO3 B aqueous NaOH C Na metal D alkaline aqueous I2 14 An organic compound has the following properties: (i) It has isomers which have identical physical properties except in the direction in which they rotate plane-polarised light. SRJC 2008 9746/01/Prelim/2008 [Turn Over C C CH3 CH3 H C H H C H H C CH3 Br C H CH2 M N CH3OCH2CH2Br CH3OCH2CN ClCH2CO2H HO2CCH2CN C6H5CHICH2CH3 C6H5CH(CN)CH2CH3 (CH3)2CHCl (CH3)2CHCN

8 (ii) It does not give a silver mirror with Tollen’s reagent (iii) It can be oxidised by acidified potassium manganate (VII) What is this organic compound? A B OCOCH3 CH CH2 CCH3CH2 OH CH3 COCH3 C D C(CH3)2OH CHO CH(CH3)OH COCH3 15 The same carboxylic acid can be obtained by the hydrolysis of a nitrile P or by oxidation of an alcohol Q. Which of the following pairs could be P and Q? P Q A CH3CH2CN CH3CH2OH B (CH3)2CHCN (CH3)3COH C C6H5CH2CN C6H5CH2CH2OH D C6H5CN C6H5OH 16 A food chemist wants to create the odour of pineapples for a product. An ester with this odour has the formula C 3H7CO2C2H5. Which of the following can be reacted to obtain the specified ester? SRJC 2008 9746/01/Prelim/2008 [Turn Over

9 A C2H5Cl and C3H7CO2H B C2H5OH and C3H7CO2H C C3H7OH and C2H5CO2H D C3H7OH and C2H5COCl 17 The compound C3H7Br undergoes a sequence of reactions as follows: C3H7Br X Y Z + Silver mirror What could be the formulae for R, S and T respectively? A CH3CH2CH2OH CH3CH2COOH CH3CH2CHO B CH3CH2CH2OH CH3CH(OH)CH2OH CH3COOH C CH3CH2CH2OH CH3CH2CHO CH3CH2COOH D CH3CH(OH)CH3 CH3COCH3 CH3COOH 18 One of the earliest biotechnological processes, developed by Weizmann in 1911, was the conversion of starch into propanone and butan-1-ol. Which reagent could be used to confirm the presence of propanone in a propanone/butan-1-ol mixture? A AgNO3 (aq) with an excess of NH3 (aq) B I2 in NaOH(aq) C acidified K2Cr2O7(aq) D Na metal 19 2-amino-4-chloro-4-oxobutanoic acid, which is an acid derivative of t he amino acids aspartic acid, and 4-hydroxylysine can be reacted with each other to form amide linkages. SRJC 2008 9746/01/Prelim/2008 [Turn Over OH-(aq) K2Cr2O7/H+ Tollen’s reagent R S T

10 H2N C C O OH H CH2 C O Cl H2N C C O OH H CH2 CH OH CH2 CH2 NH2 2-amino-4-chloro-4-oxobutanoic acid 4-hydroxylysine Determine the maximum number of different compounds, each containing one amide linkage, that can be formed from one molecule of 2-amino-4-chloro-4-oxobutanoic acid and one molecule of 4-hydroxylysine? A 1 B 2 C 3 D 4 20 The use of the Data Booklet is relevant to this question. Aluminium oxide is a stab